Using eval in a function to replace a prefix on layer names?

Question

I need to write a function where I can pass it a string and it will replace the word "prefix" in it with the contents of that string. So every time I call the function and pass it a new string i.e. alpha, beta, etc it will completely rebuild all the layers and events inside, using that key as the prefix. I suspect I need to use eval, but I'm not really sure how in this case.

layoutViews = (prefix) ->
    prefix_layer1 = new Layer
        width: 100
        height: 100

    prefix_layer1.on Events.Click ->
        buttonActions()

layoutViews(alpha)
layoutViews(beta)

I'm using CoffeeScript, but any ideas in real JS are also welcome. I realize this specific question hints at my doing something else wrong in the project, but it's mostly for my own curiosity whether this is even possible.

Answer 1

So you want

function build(prefix) {
  window[prefix + "_hi"] = function() {
    alert("hi");
  };
}

Use like this:

build("test");
test_hi();

Window is just the global (! Bad) element in browsers, so you might consider to assign to this instead of window depends on your usage.